The present invention relates to a system for packaging, handling and applying implants. Additionally, this invention relates to a method for introducing a corneal implant to the corneal surface.
Current methods and devices used to store small, delicate, and normally transparent implants entail free-floating the implant in a volume of storage fluid contained within a storage bottle or other container. This manner of storage is oftentimes used to preserve retinal transplants, brain tissue transplants, corneal implants, tissue biopsies and any other delicate biological specimen. Free-floating storage, however, subjects a stored specimen or implant to fluid agitation, which can severely and irreparably damage the integrity of the stored material. In addition, isolating transparent specimens from the storage fluid is difficult to achieve.
Corneal implants are especially susceptible to the above described problem. Corneal implants are used to correct visual disorders such as Myopia or near-sightedness, Hyperopia or far-sightedness, Presbyopia or difficulty in accommodating a change in focus, and Astigmatism. To correct these disorders, the implant is introduced into the body of the cornea in known ways, such as after a flap is formed and an under surface of the cornea is exposed. The implant, changes the shape of the cornea and alters its refractive power. These implants are generally made of various types of hydrogels, but can include other polymers, tissue implants, or the like.
In the past, storing the corneal implant required free-floating the implant in a volume of storage fluid contained within a storage container. To retrieve the implant, one had to first locate the implant within the fluid, and then remove the implant using a filter device or sequestering tool. In the case of a corneal implant, locating the implant is complicated by both the size and transparency of the implant. For instance, a corneal implant generally has a diameter of about 4.0 to 7.0 mm and a center that is normally fabricated having a thickness ranging from 25 to 50 microns. Due this minuscule size, physically grasping the implant from the storage fluid using tweezers, or the like, is simply not practical.
Successful isolation of a corneal implant, or other specimen, generally requires the use of a sieve to separate the implant from the fluid. Isolating the implant in this manner, however, subjects the implant to mechanical forces, which could lead to a loss of the implant. If not damaged, the transparent implant must still be located on the sieve surface and retrieved. The implant must therefore be grasped using tweezers, forceps, or the like. Imparting such force upon the implant, however, can also damage the implant. Using force imparting tools to hold the implant is therefore not desirable. Current isolation techniques are therefore difficult, time-consuming and create additional steps, which can also lead to implant contamination. Thus, it is desired to have an implant storage and handling system, which allows the user to rapidly and successfully retrieve the implant for prompt implantation.
Current devices used to deposit an implant onto the cornea surface generally deposit the corneal implant onto the cornea surface in a bunched or folded conformation. Aligning the implant in planar relation to the cornea surface requires the surgeon to manipulate or tease the implant so as to remove any folds or bends in the implant. Problematically, the step of unfolding the implant on the cornea surface can cause serious trauma to the cornea surface. This trauma can lead to the formation of edema, or other deleterious responses that lead to rejection or displacement of the implant.
Thus, there is believed to be a demonstrated need for a unitary packaging and handling system that provides the desired storage capabilities, easy retrieval of the specimen from that storage, and tools that are operable to retrieve and utilize the specimen without causing damage to the specimen or an implantation site. There is also an additional need for a more effective method for implanting a corneal implant onto a cornea surface.
The present invention relates to an implant packaging and handling system which includes a storage bottle having an opening to receive a volume of implant storage fluid, and an implant holding tool designed to retain the implant in fluid communication with the implant storage fluid. A storage bottle stopper holds the implant holding tool, so that a portion of the implant holding tool is immersed within the storage fluid upon placement of the stopper into the bottle, placing the implant in fluid communication with the storage fluid. The implant holding tool includes a retaining member detachably mounted to an implant applicator tool. Together they define an enclosure for retaining the implant in a secure, known storage position.
The implant applicator tool has an arcuate-shaped applicator surface with a plurality of openings. The arcuate shaped surface is contoured to correspond to the curvature of the cornea surface, which aids in the proper implantation of the implant to the cornea surface. In one embodiment, the applicator surface has one or more recessed surfaces designed to hold and center the implant on the applicator surface. One or more recessed grooves are also provided to allow fluid to flow between the implant and the applicator surface.
The openings have numerous advantages. The openings provide continuous fluid communication between a retained implant and the implant storage fluid. Upon removal from storage, the openings enable the user to unfold and orient the implant by gently passing fluid through the openings so as to float the implant into a desired central position on the applicator tool surface. Once so positioned, the user is then able to aspirate the fluid/ from between the implant and the applicator tool, thereby resting the implant firmly against the applicator tool surface. The applicator tool also includes a central opening providing the user with a reference point for centering the applicator surface, and thus, the implant onto the surface of the cornea.
The present invention also relates to a method of implanting a corneal implant using the implant packaging and handling system. The initial step includes surgically preparing the cornea surface for implantation. Next, the implant and implant holding tool are retrieved from the storage bottle, and the retaining member removed so as to provide an applicator tool together with implant. The applicator can then be attached to a handle for ease of use. The implant is then properly aligned on the applicator tool and deposited onto the surgically prepared cornea surface. Finally, the cornea is restored.